X-ray contrast media catheters are used in various medical situations to provide x-ray imagining of organs of the human body. Particularly in the field of cardiology, x-ray contrast media is applied to the heart by means of a catheter which extends therein, so that the presence of the x-ray contrast media can provide an x-ray image of the heart action and condition.
Particularly, the left ventricle is a difficult chamber of the heart to obtain x-ray imaging. At the present time, so-called pigtail catheters are used, being threaded through the aorta, around the aortic arch, and through the aortic valve until the distal tip of the catheter resides in the ventricle. Then, with the patient under an x-ray machine such as a fluoroscope, a bolus of x-ray contrast fluid is injected through the catheter at a high pressure (700-900 psi) into the ventricle, to quickly fill the ventricle with x-ray contrast media. For a moment, details of the heart structure and action become visible by x-ray imaging, until the contrast media is pumped out of the ventricle.
It has been found that, even with the best pigtail-type catheters of the prior art, difficulties have been encountered in getting good filling of the apex of the ventricle in combination with good filling of the rest of the ventricle such as the midsegmental ventricle portion. Because of this, difficulties have been obtained in obtaining accurate measurement of the ejection fraction of particularly the left ventricle. This information is critically needed for cardiologists, anesthesiologists, and surgeons as they treat heart disease.
By this invention, a catheter is provided which exhibits significant clinical improvements in the filling of heart chambers such as the left ventricle, including significantly improved apical filling. Additionally, the catheter of this invention exhibits improvements in handling and advancement through the aortic arch and the aortic valve, particularly in the situation when stenosis is present in the aortic valve.
Because of these improvements, it has become possible to obtain more accurate ejection fraction data, and to generally provide better imaging of heart structure and action, which of course provides better opportunities for accurate diagnosis and successful surgery.